Technical Field
The present invention relates to a power tool with a clamping device for axially securing a disk shaped
The present invention relates to a power tool with a clamping device for axially securing a disk shaped tool, particularly a power tool with a clamping device for axially securing a grinding wheel to a spindle of said power tool, such as angle grinder, circular saw and miter saw etc.
Background Information
In the prior art, U.S. Pat. No. 5,545,078 has disclosed a clamping device, the operating element is held between a flange which is disposed on one side of a grinding wheel and a clamping device which is disposed on the other side of said grinding wheel, a disc spring is disposed in said clamping device, further said clamping device includes a clamping and friction element, an axial ring and a disc shaped part. With a power tool have a spindle stop at an extremely high rotating speed, said stop block the spindle abruptly, shortly before it comes a dead stop, with the consequence that the grinding wheel rotates further because of its mass inertia, and the grinding wheel makes its clamping device slightly rotate with respect to the spindle and makes the clamping device loosen and the contact surface which is pressed against the grinding wheel has a tendency of departing from the grinding wheel, and because of the elastic force coming from the disc spring, the clamping device is still pressed against the grinding wheel and exerted a friction force to the grinding wheel, so as to keep itself fastened. The clamping device of this design need to be fastened after several times stops and starts, so it is inconvenient in use. If the power tool stops and starts too many times while the clamping device is not fastened, the clamping device has the possibility of loosing from the spindle, it is insecurity.